Stroke is a major cause of mortality and morbidity in the United States. Atrial fibrillation is the commonest cardiac arrhythmia, and it is associated with thrombus formation in the left atrial appendage (LAA). Migration of an atrial thrombus to the brain is a leading cause of stroke. Standard prophylactic treatment is to anti-coagulate a patient with warfarin, but anti-coagulation is often accompanied by side-effects such as bleeding and even hemorrhagic stroke. Alternative interventional devices have been developed to occlude the LAA to avoid thrombus formation. Such devices are deployed either from within the heart (such as the Watchman device or Amplatzer Cardiac Plug) or by ligating the appendage within the pericardium (such as the Lariat or Atriclip procedures). A problem with cardiac occluder devices is the need for trans-septal puncture and anticoagulation to prevent thrombus developing once the device has been deployed. A problem with existing pericardial devices is the necessity of “dry” sub-xiphoid access in the absence of prior pericardial effusions, which predisposes the patient to life-threatening bleeding complications, or the necessity of a major surgical procedure such as a thoracotomy. Another substantial problem of such existing devices is that approaches to isolate the left atrial appendage and establish countertraction to deliver endocavitary occluders or extracavitary occlusion devices or sutures risk rupture or laceration or perforation of the atrial appendage, causes immediate hemodynamic embarrassment and usually requires open surgical repair.